Zhen Yang1, Xiaoxiao Xu1, Cheng Song1. 1. Department of Respiratory Medicine, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Abstract
Background: This study aimed to investigate the function of circular RNA La-related protein 4 (circ-LARP4) on non-small cell lung cancer (NSCLC) progression. Materials and Methods: Circ-LARP4 overexpression and circ-LARP4 short hairpin RNA (shRNA) plasmids were transfected into NCI-H1650 cells and NCI-H1299 cells respectively. In rescue experiment, microRNA (miR)-21-5p overexpression and miR-21-5p shRNA plasmids were transfected into circ-LARP4 overexpression-treated NCI-H1650 cells and circ-LARP4 knockdown-treated NCI-H1650 cells, respectively. Circ-LARP4 and miR-21-5p expression levels were detected by reverse transcription-quantitative polymerase chain reaction. Cell proliferation and apoptosis were investigated by cell counting kit-8 assay and annexin V/propidium iodide assay. The interaction between circ-LARP4 and miR-21-5p was further explored by luciferase reporter assay. Results: Circ-LARP4 expression was decreased in NSCLC cell lines (including NCI-H1299, NCI-H522, NCI-H23, NCI-H358, and NCI-H1650) compared with human normal lung epithelial cell line. Circ-LARP4 overexpression inhibited cell proliferation while promoted apoptosis in NCI-H1650 cells, whereas circ-LARP4 knockdown increased cell proliferation while decreased apoptosis in NCI-H1299 cells. Meanwhile, miR-21-5p was negatively regulated by circ-LARP4, whereas circ-LARP4 was not affected by miR-21-5p in NCI-H1650 and NCI-H1299 cells. In rescue experiment, miR-21-5p overexpression attenuated the effect of circ-LARP4 overexpression on decreasing cell proliferation and increasing apoptosis in NCI-H1650 cells, whereas miR-21-5p knockdown attenuated the effect of circ-LARP4 knockdown on promoting cell proliferation and suppressing apoptosis in NCI-H1299 cells. Further luciferase reporter assay revealed that circ-LARP4 could directly bind to miR-21-5p. Conclusions: Circ-LARP4 is decreased and suppresses cell proliferation while promoted apoptosis by sponging miR-21-5p in NSCLC.
Background: This study aimed to investigate the function of circular RNA La-related protein 4 (circ-LARP4) on non-small cell lung cancer (NSCLC) progression. Materials and Methods: Circ-LARP4 overexpression and circ-LARP4 short hairpin RNA (shRNA) plasmids were transfected into NCI-H1650 cells and NCI-H1299 cells respectively. In rescue experiment, microRNA (miR)-21-5p overexpression and miR-21-5p shRNA plasmids were transfected into circ-LARP4 overexpression-treated NCI-H1650 cells and circ-LARP4 knockdown-treated NCI-H1650 cells, respectively. Circ-LARP4 and miR-21-5p expression levels were detected by reverse transcription-quantitative polymerase chain reaction. Cell proliferation and apoptosis were investigated by cell counting kit-8 assay and annexin V/propidium iodide assay. The interaction between circ-LARP4 and miR-21-5p was further explored by luciferase reporter assay. Results: Circ-LARP4 expression was decreased in NSCLC cell lines (including NCI-H1299, NCI-H522, NCI-H23, NCI-H358, and NCI-H1650) compared with human normal lung epithelial cell line. Circ-LARP4 overexpression inhibited cell proliferation while promoted apoptosis in NCI-H1650 cells, whereas circ-LARP4 knockdown increased cell proliferation while decreased apoptosis in NCI-H1299 cells. Meanwhile, miR-21-5p was negatively regulated by circ-LARP4, whereas circ-LARP4 was not affected by miR-21-5p in NCI-H1650 and NCI-H1299 cells. In rescue experiment, miR-21-5p overexpression attenuated the effect of circ-LARP4 overexpression on decreasing cell proliferation and increasing apoptosis in NCI-H1650 cells, whereas miR-21-5p knockdown attenuated the effect of circ-LARP4 knockdown on promoting cell proliferation and suppressing apoptosis in NCI-H1299 cells. Further luciferase reporter assay revealed that circ-LARP4 could directly bind to miR-21-5p. Conclusions: Circ-LARP4 is decreased and suppresses cell proliferation while promoted apoptosis by sponging miR-21-5p in NSCLC.